Probably not. The IRS doesn't get copies of your invoices. If your client was audited they might look at it to verify amounts. The IRS doesn't know who you've billed or how much that person paid you. That only comes up if you receive a 1099. If you ever come under real scrutiny, they'll grab your bank statements, that's where all the information is.What I'm trying to ask is, when I make a invoice to customer and that customer uses it as a deduction, will that invoice ever comeback to haunt me if didn't claim on my taxes?